The typical occupancy of the buildings was 50k workers and another few tens of thousands were going through it as visitors/tourists [0]. At the time of the attack there were only ~15K inside the buildings. Of those ~2k were killed.
[0] I had a picture of me on the roof two days before the attack.
I almost visited them the week before, but we were running late and didn't have time on that trip.
My Sept 11 experience was not actually realizing anything was really wrong until the afternoon.
I had classes all morning that semester; there were snippets of conversation, a "did you hear" buzz, but nothing really penetrated until I got back to the dorm and found my roommate glued to the TV.
- NIST followed by a peer-reviewed summary in the Journal of Structural Engineering
There's no world in which a burning building not hit by a plane would fall as if it was demolished. Sorry to break the news for you.
Probably one of the comments that aged the worse in the entire internet